Merge master.kernel.org:/home/rmk/linux-2.6-arm
[linux-2.6] / arch / arm / mach-integrator / clock.c
1 /*
2  *  linux/arch/arm/mach-integrator/clock.c
3  *
4  *  Copyright (C) 2004 ARM Limited.
5  *  Written by Deep Blue Solutions Limited.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/list.h>
14 #include <linux/errno.h>
15 #include <linux/err.h>
16 #include <linux/string.h>
17
18 #include <asm/semaphore.h>
19 #include <asm/hardware/clock.h>
20 #include <asm/hardware/icst525.h>
21
22 #include "clock.h"
23
24 static LIST_HEAD(clocks);
25 static DECLARE_MUTEX(clocks_sem);
26
27 struct clk *clk_get(struct device *dev, const char *id)
28 {
29         struct clk *p, *clk = ERR_PTR(-ENOENT);
30
31         down(&clocks_sem);
32         list_for_each_entry(p, &clocks, node) {
33                 if (strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
34                         clk = p;
35                         break;
36                 }
37         }
38         up(&clocks_sem);
39
40         return clk;
41 }
42 EXPORT_SYMBOL(clk_get);
43
44 void clk_put(struct clk *clk)
45 {
46         module_put(clk->owner);
47 }
48 EXPORT_SYMBOL(clk_put);
49
50 int clk_enable(struct clk *clk)
51 {
52         return 0;
53 }
54 EXPORT_SYMBOL(clk_enable);
55
56 void clk_disable(struct clk *clk)
57 {
58 }
59 EXPORT_SYMBOL(clk_disable);
60
61 int clk_use(struct clk *clk)
62 {
63         return 0;
64 }
65 EXPORT_SYMBOL(clk_use);
66
67 void clk_unuse(struct clk *clk)
68 {
69 }
70 EXPORT_SYMBOL(clk_unuse);
71
72 unsigned long clk_get_rate(struct clk *clk)
73 {
74         return clk->rate;
75 }
76 EXPORT_SYMBOL(clk_get_rate);
77
78 long clk_round_rate(struct clk *clk, unsigned long rate)
79 {
80         struct icst525_vco vco;
81
82         vco = icst525_khz_to_vco(clk->params, rate / 1000);
83         return icst525_khz(clk->params, vco) * 1000;
84 }
85 EXPORT_SYMBOL(clk_round_rate);
86
87 int clk_set_rate(struct clk *clk, unsigned long rate)
88 {
89         int ret = -EIO;
90         if (clk->setvco) {
91                 struct icst525_vco vco;
92
93                 vco = icst525_khz_to_vco(clk->params, rate / 1000);
94                 clk->rate = icst525_khz(clk->params, vco) * 1000;
95
96                 printk("Clock %s: setting VCO reg params: S=%d R=%d V=%d\n",
97                         clk->name, vco.s, vco.r, vco.v);
98
99                 clk->setvco(clk, vco);
100                 ret = 0;
101         }
102         return 0;
103 }
104 EXPORT_SYMBOL(clk_set_rate);
105
106 /*
107  * These are fixed clocks.
108  */
109 static struct clk kmi_clk = {
110         .name   = "KMIREFCLK",
111         .rate   = 24000000,
112 };
113
114 static struct clk uart_clk = {
115         .name   = "UARTCLK",
116         .rate   = 14745600,
117 };
118
119 int clk_register(struct clk *clk)
120 {
121         down(&clocks_sem);
122         list_add(&clk->node, &clocks);
123         up(&clocks_sem);
124         return 0;
125 }
126 EXPORT_SYMBOL(clk_register);
127
128 void clk_unregister(struct clk *clk)
129 {
130         down(&clocks_sem);
131         list_del(&clk->node);
132         up(&clocks_sem);
133 }
134 EXPORT_SYMBOL(clk_unregister);
135
136 static int __init clk_init(void)
137 {
138         clk_register(&kmi_clk);
139         clk_register(&uart_clk);
140         return 0;
141 }
142 arch_initcall(clk_init);